A German court has handed YMTC a victory in its long-running patent battle with Micron, ruling on September 18 that Micron infringed two of YMTC's 3D NAND utility models. The injunctions, issued by the Munich 1 Regional Court, could restrict Micron's ability to supply certain NAND products in Germany and potentially affect the broader European market. The rulings are first-instance only, and Micron has already filed an appeal with the Munich Higher Regional Court, which could suspend the injunctions.
The German cases are just one front in a legal war that began in 2023, when YMTC sued Micron in California over eight 3D NAND architecture patents. Since then, the dispute has expanded to more than 20 patents, with suits and countersuits covering infringement, declaratory judgment, invalidation, and even libel and false advertising. Courts in China, the U.S., the U.K., and Germany have been drawn in, and seven of the disputed patents have already been declared invalid. Micron denies any wrongdoing and says it will keep challenging the validity of YMTC's patents.
The fight over 3D NAND technology—which stacks memory cells vertically to increase density and lower cost per bit—carries significant commercial weight. It also unfolds against the backdrop of broader U.S.-China tech tensions, with Washington restricting China's access to advanced chipmaking tools and Beijing limiting exports of critical raw materials. While today's ruling is a win for YMTC in Germany, the final outcome remains far from settled as appeals and validity challenges continue across multiple jurisdictions.